How to monitor update loop timing?

Is there a way to get a system timestamp of 'when' gazebo returns a state [before deadline or not], and actually check the jitter / determinism? I tried to look through the documentation but couldn't find such a feature. I imagine if the simulation is simple enough, the physics calculations could be fast enough, but I'm not sure if that can be used to test for a pseudo-deterministic timing of the update loops. Keeping track of this statistic will allow tuning of the models to make sure that we don't overshoot the timing deadlines due to complexity.